Krebs on Security

In-depth security news and investigation

Posts Tagged: Blackberry

Multiple security firms recently identified cryptocurrency mining service Coinhive as the top malicious threat to Web users, thanks to the tendency for Coinhive’s computer code to be used on hacked Web sites to steal the processing power of its visitors’ devices. This post looks at how Coinhive vaulted to the top of the threat list less than a year after its debut, and explores clues about the possible identities of the individuals behind the service.

Coinhive is a cryptocurrency mining service that relies on a small chunk of computer code designed to be installed on Web sites. The code uses some or all of the computing power of any browser that visits the site in question, enlisting the machine in a bid to mine bits of the Monero cryptocurrency.

Monero differs from Bitcoin in that its transactions are virtually untraceble, and there is no way for an outsider to track Monero transactions between two parties. Naturally, this quality makes Monero an especially appealing choice for cybercriminals.

Coinhive released its mining code last summer, pitching it as a way for Web site owners to earn an income without running intrusive or annoying advertisements. But since then, Coinhive’s code has emerged as the top malware threat tracked by multiple security firms. That’s because much of the time the code is installed on hacked Web sites — without the owner’s knowledge or permission.

Much like a malware infection by a malicious bot or Trojan, Coinhive’s code frequently locks up a user’s browser and drains the device’s battery as it continues to mine Monero for as long a visitor is browsing the site.

According to publicwww.com, a service that indexes the source code of Web sites, there are nearly 32,000 Web sites currently running Coinhive’s JavaScript miner code. It’s impossible to say how many of those sites have installed the code intentionally, but in recent months hackers have secretly stitched it into some extremely high-profile Web sites, including sites for such companies as The Los Angeles Times, mobile device maker Blackberry, Politifact, and Showtime.

And it’s turning up in some unexpected places: In December, Coinhive code was found embedded in all Web pages served by a WiFi hotspot at a Starbucks in Buenos Aires. For roughly a week in January, Coinhive was found hidden inside of YouTube advertisements (via Google’s DoubleClick platform) in select countries, including Japan, France, Taiwan, Italy and Spain. In February, Coinhive was found on “Browsealoud,” a service provided by Texthelp that reads web pages out loud for the visually impaired. The service is widely used on many UK government websites, in addition to a few US and Canadian government sites.

What does Coinhive get out of all this? Coinhive keeps 30 percent of whatever amount of Monero cryptocurrency that is mined using its code, whether or not a Web site has given consent to run it. The code is tied to a special cryptographic key that identifies which user account is to receive the other 70 percent.

Coinhive does accept abuse complaints, but it generally refuses to respond to any complaints that do not come from a hacked Web site’s owner (it mostly ignores abuse complaints lodged by third parties). What’s more, when Coinhive does respond to abuse complaints, it does so by invalidating the key tied to the abuse.

But according to Troy Mursch, a security expert who spends much of his time tracking Coinhive and other instances of “cryptojacking,” killing the key doesn’t do anything to stop Coinhive’s code from continuing to mine Monero on a hacked site. Once a key is invalidated, Mursch said, Coinhive keeps 100 percent of the cryptocurrency mined by sites tied to that account from then on.

Mursch saidCoinhive appears to have zero incentive to police the widespread abuse that is leveraging its platform.

“When they ‘terminate’ a key, it just terminates the user on that platform, it doesn’t stop the malicious JavaScript from running, and it just means that particular Coinhive user doesn’t get paid anymore,” Mursch said. “The code keeps running, and Coinhive gets all of it. Maybe they can’t do anything about it, or maybe they don’t want to. But as long as the code is still on the hacked site, it’s still making them money.”

Reached for comment about this apparent conflict of interest, Coinhive replied with a highly technical response, claiming the organization is working on a fix to correct that conflict.

“We have developed Coinhive under the assumption that site keys are immutable,” Coinhive wrote in an email to KrebsOnSecurity. “This is evident by the fact that a site key can not be deleted by a user. This assumption greatly simplified our initial development. We can cache site keys on our WebSocket servers instead of reloading them from the database for every new client. We’re working on a mechanism [to] propagate the invalidation of a key to our WebSocket servers.”

AUTHEDMINE

Coinhive has responded to such criticism by releasing a version of their code called “AuthedMine,” which is designed to seek a Web site visitor’s consent before running the Monero mining scripts. Coinhive maintains that approximately 35 percent of the Monero cryptocurrency mining activity that uses its platform comes from sites using AuthedMine.

But according to a report published in February by security firm Malwarebytes, the AuthedMine code is “barely used” compared to the use of Coinhive’s mining code that does not seek permission from Web site visitors. Malwarebytes’ telemetry data (drawn from antivirus alerts when users browse to a site running Coinhive’s code) determined that AuthedMine is used in a little more than one percent of all cases that involve Coinhive’s mining code.

Image: Malwarebytes. The statistic above refer to the number of times per day between Jan. 10 and Feb. 7 that Malwarebytes blocked connections to AuthedMine and Coinhive, respectively.

Asked to comment on the Malwarebytes findings, Coinhive replied that if relatively few people are using AuthedMine it might be because anti-malware companies like Malwarebytes have made it unprofitable for people to do so.

“They identify our opt-in version as a threat and block it,” Coinhive said. “Why would anyone use AuthedMine if it’s blocked just as our original implementation? We don’t think there’s any way that we could have launched Coinhive and not get it blacklisted by Antiviruses. If antiviruses say ‘mining is bad,’ then mining is bad.”

WHO IS COINHIVE?

[Author’s’ note: Ordinarily, I prefer to link to sources of information cited in stories, such as those on Coinhive’s own site and other entities mentioned throughout the rest of this piece. However, because many of these links either go to sites that actively mine with Coinhive or that include decidedly not-safe-for-work content, I have included screenshots instead of links in these cases. For these reasons, I would strongly advise against visiting pr0gramm’s Web site.]

According to a since-deleted statement on the original version of Coinhive’s Web site — coin-hive[dot]com — Coinhive was born out of an experiment on the German-language image hosting and discussion forum pr0gramm[dot]com.

A now-deleted “About us” statement on the original coin-hive[dot]com Web site. This snapshop was taken on Sept. 15, 2017. Image courtesy archive.org.

Indeed, multiple discussion threads on pr0gramm[dot]com show that Coinhive’s code first surfaced there in the third week of July 2017. At the time, the experiment was dubbed “pr0miner,” and those threads indicate that the core programmer responsible for pr0miner used the nickname “int13h” on pr0gramm. In a message to this author, Coinhive confirmed that “most of the work back then was done by int13h, who is still on our team.”

I asked Coinhive for clarity on the disappearance of the above statement from its site concerning its affiliation with pr0gramm. Coinhive replied that it had been a convenient fiction:

“The owners of pr0gramm are good friends and we’ve helped them with their infrastructure and various projects in the past. They let us use pr0gramm as a testbed for the miner and also allowed us to use their name to get some more credibility. Launching a new platform is difficult if you don’t have a track record. As we later gained some publicity, this statement was no longer needed.”

Asked for clarification about the “platform” referred to in its statement (“We are self-funded and have been running this platform for the past 11 years”) Coinhive replied, “Sorry for not making it clearer: ‘this platform’ is indeed pr0gramm.”

After receiving this response, it occurred to me that someone might be able to find out who’s running Coinhive by determining the identities of the pr0gramm forum administrators. I reasoned that if they were not one and the same, the pr0gramm admins almost certainly would know the identities of the folks behind Coinhive. Continue reading →

A little-known feature of many modern smartphones is their ability to duplicate video on the device’s screen so that it also shows up on a much larger display — like a TV. However, new research shows that this feature may quietly expose users to a simple and cheap new form of digital eavesdropping.

Dubbed “video jacking” by its masterminds, the attack uses custom electronics hidden inside what appears to be a USB charging station. As soon as you connect a vulnerable phone to the appropriate USB charging cord, the spy machine splits the phone’s video display and records a video of everything you tap, type or view on it as long as it’s plugged in — including PINs, passwords, account numbers, emails, texts, pictures and videos.

Some of the equipment used in the “video jacking” demonstration at the DEF CON security conference last week in Las Vegas. Source: Brian Markus.

[Click here if you’re the TL;DR type and just want to know if your phone is at risk from this attack.]

Demonstrations of this simple but effective mobile spying technique were on full display at the DEF CON security conference in Las Vegas last week. I was busy chasing a story at DEF CON unrelated to the conference this year, so I missed many people and talks that I wanted to see. But I’m glad I caught up with the team behind DEF CON’s annual and infamous “Wall of Sheep,” a public shaming exercise aimed at educating people about the dangers of sending email and other plain text online communications over open wireless networks.

“Juice jacking” refers to the ability to hijack stored data when the user unwittingly plugs his phone into a custom USB charging station filled with computers that are ready to suck down and record said data (both Android and iOS phones now ask users whether they trust the computer before allowing data transfers).

In contrast, video jacking lets the attacker record every key and finger stroke the user makes on the phone, so that the owner of the evil charging station can later replay the videos and see any numbers or keys pressed on the smart phone.

That’s because those numbers or keys will be raised briefly on the victim’s screen with each key press. Here’s an example: While the user may have enabled a special PIN that needs to be entered before the phone unlocks to the home screen, this method captures even that PIN as long as the device is vulnerable and plugged in before the phone is unlocked.

GREAT. IS MY PHONE VULNERABLE?

Most of the phones vulnerable to video jacking are Android or other HDMI-ready smartphones from Asus, Blackberry, HTC, LG, Samsung, and ZTE.This page of HDMI enabled smartphones at phonerated.com should not be considered all-inclusive. Here’s another list. When in doubt, search online for your phone’s make and model to find out if it is HDMI or MHL ready.

Video jacking is a problem for users of HDMI-ready phones mainly because it’s very difficult to tell a USB cord that merely charges the phone versus one that also taps the phone’s video-out capability. Also, there’s generally no warning on the phone to alert the user that the device’s video is being piped to another source, Markus said.

“All of those phones have an HDMI access feature that is turned on by default,” he said. “A few HDMI-ready phones will briefly flash something like ‘HDMI Connected’ whenever they’re plugged into a power connection that is also drawing on the HDMI feature, but most will display no warning at all. This worked on all the phones we tested with no prompting.”

Both Markus and Rowley said they did not test the attack against Apple iPhones prior to DEF CON, but today Markus said he tested it at an Apple store and the video of the iPhone 6’s home screen popped up on the display in the store without any prompt. Getting it to work on the display required a special lightning digital AV adapter from Apple, which could easily be hidden inside an evil charging station and fed an extension adapter and then a regular lightning cable in front of that.

An attack late last week that compromised the personal and business Gmail accounts of Matthew Prince, chief executive of Web content delivery system CloudFlare, revealed a subtle but dangerous security flaw in the 2-factor authentication process used in Google Apps for business customers. Google has since fixed the glitch, but the incident offers a timely reminder that two-factor authentication schemes are only as secure as their weakest component.

In a blog post on Friday, Prince wrote about a complicated attack in which miscreants were able to access a customer’s account on CloudFlare and change the customer’s DNS records. The attack succeeded, Prince said, in part because the perpetrators exploited a weakness in Google’s account recovery process to hijack his CloudFlare.com email address, which runs on Google Apps.

A Google spokesperson confirmed that the company “fixed a flaw that, under very specific conditions, existed in the account recovery process for Google Apps for Business customers.”

“If an administrator account that was configured to send password reset instructions to a registered secondary email address was successfully recovered, 2-step verification would have been disabled in the process,” the company said. “This could have led to abuse if their secondary email account was compromised through some other means. We resolved the issue last week to prevent further abuse.”

Prince acknowledged that the attackers also leveraged the fact that his recovery email address — his personal Gmail account — was not taking advantage of Google’s free 2-factor authentication offering. Prince claims that the final stage of the attack succeeded because the miscreants were able to trick his mobile phone provider — AT&T — into forwarding his voicemail to another account.

In a phone interview Monday, Prince said he received a phone call at 11:39 a.m. on Friday from a phone number in Chico, Calif. Not knowing anyone from that area, he let the call go to voicemail. Two minutes later, he received a voicemail that was a recorded message from Google saying that his personal Gmail account password had been changed. Prince said he then initiated the account recovery process himself and changed his password back, and that the hacker(s) and he continued to ping pong for control over the Gmail account, exchanging control 10 times in 15 minutes.

“The calls were being forwarded, because phone calls still came to me,” Prince said. “I didn’t realize my voicemail had been compromised until that evening when someone called me and soon after got a text message saying, ‘Hey, something is weird with your voicemail.'”

Gmail constantly nags users to tie a mobile phone number to their account, ostensibly so that those who forget their passwords or get locked out can have an automated, out-of-band way to receive a password reset code (Google also gets another way to link real-life identities connected to cell phone records with Gmail accounts that may not be so obviously tied to a specific identity). The default method of sending a reset code is via text message, but users can also select to receive the prompt via a phone call from Google.

The trouble is, Gmail users who haven’t availed themselves of Google’s 2-factor authentication offering (Google calls it “2-step verification”) are most likely at the mercy of the security of their mobile provider. For example, AT&T users who have not assigned a PIN to their voicemail accounts are vulnerable to outsiders listening to their voice messages, simply by spoofing the caller ID so that it matches the target’s own phone number. Prince said his AT&T PIN was a completely random 24-digit combination (and here I thought I was paranoid with a 12-digit PIN).

“Working with Google we believe we have discovered the vulnerability that allowed the hacker to access my personal Gmail account, which was what began the chain of events,” Prince wrote in an update to the blog post about the attack. “It appears to have involved a breach of AT&T’s systems that compromised the out-of-band verification. The upshot is that if an attacker knows your phone number and your phone number is listed as a possible recovery method for your Google account then, at best, your Google account may only be as secure as your voicemail PIN.”